Swimming pool



FIG. 1 is a front view of a swimming pool embodying my new design;

FIG. 2 is a right or left side view of FIG. 1;

FIG. 3 is a top plan view of FIG. 1;

FIG. 4 is a bottom plan view;

FIG. 5 is a perspective plan view. 

The ornamental design for a swimming pool, as shown and described. 